1. Field of the Invention
The present invention relates to a heater lamp control apparatus and method, and more particularly, to a heater lamp control apparatus and method to detect an inputted AC voltage and to provide a pulse signal to correspond thereto, so that a heater lamp control signal corresponding to a phase of a voltage over a predetermined level from the inputted AC voltage may be outputted.
2. Description of the Related Art
In general, an electrophotographic printer is provided with a photosensitive drum, a developing unit, a transfer unit, and a fixing unit. The tranfer unit is a unit to transfer onto a recording sheet of paper, an image formed on the photosensitive drum by a developing agent through the developing unit, and the fixing unit is a unit to fix the image transferred on the recording sheet. The fixing unit is provided to heat a surface of a fixing roller to a certain temperature. The fixing roller is mounted separately from a transfer roller to press and forward the recording sheet moving past the transfer roller. An AC voltage-driven heater lamp is generally used as a heating device to heat the surface of the fixing roller to a certain temperature.
In the related art, an AC voltage is applied to the heater lamp regardless of a phase of the applied AC voltage. Accordingly, a control unit outputs a heater lamp control signal unrelated to the phase of the AC voltage to turn on and off the application of the AC voltage, so that the phase of the AC voltage has no connection with the heater lamp control signal. Therefore, it is impossible to precisely control the applications of the AC voltage. That is, since the phases of the AC voltage may not be properly distributed, it becomes impossible to precisely control the applications of the AC voltage to be turned on and off, causing a flickering phenomenon that temporarily lowers an electric power supplied to peripheral circuits, and resulting in a problem of adversely affecting operations and stabilities of other devices provided with the peripheral circuits.